AX 2012 - How to view the Form Level ManagedHost Control - C# Code

Hi to All,

How to view the form- ManagedHost control Events Code.

I gone through one std form(HcmBenefitEligibilityPolicy), in that they used one managedhost control.

I found the below assembly lannguage in properties.

Microsoft.Dynamics.Framework.Expression.AxExpressionBuilder

I need to add some another validation in that control.

I tried few hours to view the code for that Assembly lanaguage but i can able to find only DLL file.

With that DLL file i can’t able to view the real .net Code.

I want to know that C# code.

Please help me to solve…

Thank to all…